The fluctuations of the Higgs and pseudo Nambu-Goldstone fields in the 2-flavor color superconductivity (2SC) phase with mismatched pairing are described in the nonlinear realization framework of the gauged Nambu-Jona-Lasinio model. In the gapless 2SC phase, not only Nambu-Goldstone currents can be spontaneously generated, but also the Higgs field exhibits instablity. The Nambu-Goldstone currents generation indicates the formation of the single plane wave Larkin-Ovchinnikov-Fulde-Ferrel state and breaks rotation symmetry, while the Higgs instability favors spatial inhomogeneity and breaks translation invariance. In this paper, we focus on the Higgs instability which has not drawn much attention yet. The Higgs instability cannot be removed without a long range force, thus it persists in the gapless superfluidity and induces phase separation. In the case of gapless 2-flavor color superconductivity state, the Higgs instability can only be partially removed by the electric Coulomb energy. However, it is not excluded that the Higgs instability might be completely removed in the charge neutral gapless color-flavor locked phase by the color Coulomb energy.

We have shown in a previous paper that two identical detectors with each fiducial mass of 0.27 megaton water, one in Kamioka and the other in Korea, which receive the (anti-) muon neutrino beam of 4 MW power from J-PARC facility have potential of determining the neutrino mass hierarchy and discovering $CP$ violation by resolving the degeneracies associated with them. In this paper, we point out that the same setting has capability of resolving the ${\theta }_{23}$ octant degeneracy in region where ${sin}^{2}2{\theta }_{23}\lesssim 0.97$ at 2 standard deviation confidence level even for very small values of ${\theta }_{13}$. Altogether, it is demonstrated that one can solve all the eightfold neutrino parameter degeneracies in situ by using the Tokai-to-Kamioka-Korea setting if ${\theta }_{13}$ is within reach by the next generation superbeam experiments. We also prove the property called “decoupling between the degeneracies”, which is valid to first-order in perturbation theory of the earth matter effect, that guarantees approximate independence between analyses to solve any one of the three different type of degeneracies.

In this letter we explore the Higgs instability in the gapless superfluid/superconducting phase. This is in addition to the (chromo)magnetic instability that is related to the fluctuations of the Nambu-Goldstone bosonic fields. While the latter may induce a single-plane-wave Larkin-Ovchinnikov-Fulde-Ferrel state, the Higgs instability favors spatial inhomogeneity. In the case of the 2-flavor color superconductivity state the Higgs instability can only be partially removed by the electric Coulomb energy. But this does not exclude the possibility that it can be completely removed in other exotic states such as the gapless color-flavor locked state.

We present solutions of coupled particle-field evolution in classical U(1) and SU(2) gauge theories in real time on three-dimensional lattices. Our simulations are performed in a regime of extreme anisotropy of the momentum distribution of hard particles where backreaction is important. We find qualitatively different behavior for the two theories when the field strength is high enough that non-Abelian self-interactions matter for SU(2). It appears that the energy drained by a Weibel-like plasma instability from the particles does not build up exponentially in soft transverse magnetic fields but instead returns, isotropically, to the hard scale via a rapid avalanche into the ultraviolet.

We construct a new class of ($n+1$)-dimensional ($n\ge 3$) black hole solutions in Einstein-Born-Infeld-dilaton gravity with Liouville-type potential for the dilaton field and investigate their properties. These solutions are neither asymptotically flat nor (anti)-de Sitter. We find that these solutions can represent black holes, with inner and outer event horizons, an extreme black hole, or a naked singularity provided the parameters of the solutions are chosen suitably. We compute the thermodynamic quantities of the black hole solutions and find that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis and investigate the effect of dilaton on the stability of the solutions.

We use a low redshift expansion of the cosmological equations of extended (scalar-tensor) quintessence to divide the observable Hubble history parameter space in four sectors: A forbidden sector I where the scalar field of the theory becomes imaginary (the kinetic term becomes negative), a forbidden sector II where the scalar field rolls up (instead of down) its potential, an allowed “freezing” quintessence sector III where the scalar field is currently decelerating down its potential towards freezing and an allowed “thawing” sector IV where the scalar field is currently accelerating down its potential. The dividing lines between the sectors depend sensitively on the time derivatives of the Newton’s constant $G$ over powers of the Hubble parameter. For minimally coupled quintessence which appears as a special case for a constant $G$ our results are consistent with previous studies. Observable parameter ${\chi }^2$ contours based on current data (Supernova Legacy Survey data set) are also constructed on top of the sectors, for a prior of ${\Omega }_m=0.24$. By demanding that the observed $2\sigma$ ${\chi }^2$ parameter contours do not lie entirely in the forbidden sectors, we derive stringent constraints on the current second time derivative of Newton’s constant $G$. In particular, we find $\frac{\ddot{G}}{G}>-1.91H_0^2=-2\times {10}^{-20}{h}^2{\mathrm{yrs}}^{-2}$ at the $2\sigma$ level which is complementary to solar system tests which constrain only the first derivative of $G$ as $|\frac{\dot{G}}{G}|<{10}^{-14}{\mathrm{yrs}}^{-1}$ at $1\sigma$.

We show that a contracting universe which bounces due to quantum cosmological effects and connects to the hot big-bang expansion phase, can produce an almost scale invariant spectrum of perturbations provided the perturbations are produced during an almost matter dominated era in the contraction phase. This is achieved using Bohmian solutions of the canonical Wheeler-DeWitt equation, thus treating both the background and the perturbations in a fully quantum manner. We find a very slightly blue spectrum ($n_{\mathrm{S}}-1>0$). Taking into account the spectral index constraint as well as the cosmic microwave background normalization measure yields an equation of state that should be less than $\omega \lesssim 8\times {10}^{-4}$, implying $n_{\mathrm{S}}-1\sim \mathcal{O}({10}^{-4})$, and that the characteristic curvature scale of the Universe at the bounce is $L_0\sim {10}^3{\ell }_{\mathrm{Pl}}$, a region where one expects that the Wheeler-DeWitt equation should be valid without being spoiled by string or loop quantum gravity effects. We have also obtained a consistency relation between the tensor-to-scalar ratio $T/S$ and the scalar spectral index as $T/S\sim 4.6\times {10}^{-2}\sqrt{n_{\mathrm{S}}-1}$, leading to potentially measurable differences with inflationary predictions.

In the present work we study numerically quasiequatorial lensing by the charged, stationary, axially symmetric Kerr-Sen dilaton-axion black hole in the strong deflection limit. In this approximation we compute the magnification and the positions of the relativistic images. The most outstanding effect is that the Kerr-Sen black hole caustics drift away from the optical axis and shift in the clockwise direction with respect to the Kerr caustics. The intersections of the critical curves on the equatorial plane as a function of the black hole angular momentum are found, and it is shown that they decrease with the increase of the parameter $Q^2/M$. All of the lensing quantities are compared to particular cases as Schwarzschild, Kerr, and Gibbons-Maeda black holes.

The deconfinement transition is studied close to the continuum limit of $SO(3)$ lattice gauge theory. High barriers for tunneling among different twist sectors causing loss of ergodicity for local update algorithms are circumvented by means of parallel tempering. We compute monopole and center vortex free energies both within the confining phase and through the deconfinement transition. We discuss in detail the general problem of defining order parameters for adjoint actions.

With a consistent definition of transverse-momentum dependent (TMD) light-cone wave function, we show that the amplitude for the process ${\gamma }^{*}{\pi }^0\to \gamma$ can be factorized when the virtuality of the initial photon is large. In contrast to the collinear factorization in which the amplitude is factorized as a convolution of the standard light-cone wave function and a hard part, the TMD factorization yields a convolution of a TMD light-cone wave function, a soft factor and a hard part. We explicitly show that the TMD factorization holds at one-loop level. It is expected that the factorization holds beyond one-loop level because the cancellation of soft divergences is on a diagram-by-diagram basis. We also show that the TMD factorization helps to resum large logarithms of type ${ln}^{2}x$.

We first extract the binding energy $\overline{\Lambda }$ and decay constants of the $D$ wave heavy meson doublets $(1^{-},2^{-})$ and $(2^{-},3^{-})$ with QCD sum rule in the leading order of heavy quark effective theory. Then we study their pionic $(\pi ,K,\eta )$ couplings using the light-cone sum rule, from which the parameter $\overline{\Lambda }$ can also be extracted. We then calculate the pionic decay widths of the strange/nonstrange $D$ wave heavy $D/B$ mesons and discuss the possible candidates for the $D$ wave charm-strange mesons. Further experimental information, such as the ratio between $D_s\eta$ and $DK$ modes, will be very useful to distinguish various assignments for $D_{sJ}(2860\hspace{0.17em}2715)$.

I study the incorporation of renormalization group (RG) improved BFKL kernels in the Balitsky-Kovchegov (BK) equation which describes parton saturation. The RG improvement takes into account important parts of the next-to-leading and higher-order logarithmic corrections to the kernel. The traveling wave front method for analyzing the BK equation is generalized to deal with RG-resummed kernels, restricting to the interesting case of fixed QCD coupling. The results show that the higher-order corrections suppress the rapid increase of the saturation scale with increasing rapidity. I also perform a diffusive differential equation approximation, which illustrates that some important qualitative properties of the kernel change when including RG corrections.

Precise measurements of the spin structure functions of the proton $g_1^p(x,Q^2)$ and deuteron $g_1^d(x,Q^2)$ are presented over the kinematic range $0.0041\le x\le 0.9$ and $0.18{\mathrm{GeV}}^2\le Q^2\le 20{\mathrm{GeV}}^2$. The data were collected at the HERMES experiment at DESY, in deep-inelastic scattering of 27.6 GeV longitudinally polarized positrons off longitudinally polarized hydrogen and deuterium gas targets internal to the HERA storage ring. The neutron spin structure function $g_1^n$ is extracted by combining proton and deuteron data. The integrals of $g_1^{p,d}$ at $Q^2=5{\mathrm{GeV}}^2$ are evaluated over the measured $x$ range. Neglecting any possible contribution to the $g_1^d$ integral from the region $x\le 0.021$, a value of $0.330\pm 0.011(\mathrm{theo})\pm 0.025(\exp )\pm 0.028(\mathrm{evol})$ is obtained for the flavor-singlet axial charge $a_0$ in a leading-twist next-to-next-to-leading-order analysis.

In this article we construct cylindrical thin-shell wormholes in the context of global cosmic strings. We study the stability of static configurations under perturbations preserving the symmetry and we find that the throat tends to collapse or expand, depending only on the direction of the velocity perturbation.

The boundary of the first order chiral phase transition region is studied in the $m_{\pi }-m_K-{\mu }_B$ space using the one-loop optimized perturbation theory for the resummation of the perturbative series. Chiral perturbation theory for mesons and baryons is used for the $T=0$ parametrization of the model. The surface of second order transition points bends with increasing ${\mu }_B$ towards the physical point of the $m_{\pi }-m_K$ mass plane allowing for the existence of the critical end point in the ${\mu }_B-T$ plane at the physical point. The location and scaling region of the CEP is explored.

Using diagrammatic methods, we show how the Ward identity can be used to constrain the ladder kernel in transport coefficient calculations. More specifically, we use the Ward identity to determine the necessary diagrams that must be resummed using an integral equation. One of our main results is an equation relating the kernel of the integral equation with functional derivatives of the full self-energy; it is similar to what is obtained with two-particle irreducible (2PI) effective action methods. However, since we use the Ward identity as our starting point, gauge invariance is preserved. Using power counting arguments, we also show which self-energies must be included in the resummation at leading order, including 2 to 2 scatterings and 1 to 2 collinear scatterings with the Landau-Pomeranchuk-Migdal effect. We show that our quantum field theory result is equivalent to the one of Arnold, Moore, and Yaffe obtained using effective kinetic theory. In this paper we restrict our discussion to electrical conductivity in hot QED, but our method can in principle be generalized to other transport coefficients and other theories.

We suggest a possible algorithm to calculate one-loop $n$-point functions within a variant of light-front perturbation theory. The key ingredients are the covariant Passarino-Veltman scheme and a surprising integration formula that localizes Feynman integrals at vanishing longitudinal momentum. The resulting expressions are generalizations of Weinberg’s infinite-momentum results and are manifestly Lorentz invariant. For $n=2$ and 3 we explicitly show how to relate those to light-front integrals with standard energy denominators. All expressions are rendered finite by means of transverse dimensional regularization.

We uniquely determine the infrared asymptotics of Green functions in Landau gauge Yang-Mills theory. They have to satisfy both the Dyson-Schwinger equations and functional renormalization group equations. Then, the requirement of consistency fixes the relation between the infrared power laws of these Green functions. We discuss consequences for the interpretation of recent results from lattice QCD.

We study the scenario where a sneutrino is the next to lightest supersymmetric particle (NLSP) which decays into a gravitino and standard model particles. The daughter particles such as neutrinos and quarks cause electromagnetic and hadronic showers and affect big-bang nucleosynthesis. It is found that, despite a small branching ratio, four-body processes including quarks in the final state give the most stringent constraint on the sneutrino abundance for gravitino mass of 1–100 GeV. Pion production by high-energy neutrinos is important when the sneutrinos decay at $\sim 1\sec$. We also discuss the thermal leptogenesis in the sneutrino NLSP scenario.

In this paper we present an effort to extend the LLM construction of $1/2$ BPS states in minimal IIB supergravity to configurations that preserve $1/4$ of the total number of supersymmetries. Following the same techniques we reduce the problem to that of a single scalar which satisfies a nonlinear equation. In particular, the scalar is identified to be the Kahler potential with which a four dimensional base space is equipped.